<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8">
    <title></title>
    <style>
        .box {
            width: 400px;
            margin:100px auto;
            border:1px solid #ccc;
        }
        .bottom div{
            width:100%;
            height: 300px;
            background-color: pink;
            display: none;
        }
        .purple {
            background-color: purple;
        }
    </style>
</head>
<body>
<div class="box">
    <div class="top">
        <button>第一个</button>
        <button>第二个</button>
        <button>第三个</button>
        <button>第四个</button>
        <button>第五个</button>
    </div>
    <div class="bottom">
        <div style="display: block;">1好盒子</div>
        <div>2好盒子</div>
        <div>3好盒子</div>
        <div>4好盒子</div>
        <div>5好盒子</div>
    </div>
</div>

</body>
</html>